The present invention relates to the development and manufacture of the equipment based on microelectronics items and semiconductor devices, and can be widely used for checking and rejecting IC chips prior to their mounting into packages or as a part of multichip modules, as well as for mounting chips into packages or multichip modules. The invention is directed onto reducing the cost of rejecting procedures for chips, for decreasing the labor content of equipment assembly mounting processes, for increasing a yield percentage of fit items, and also for raising a chip operation reliability in the equipment.
An application of this invention seems to be especially prospective in manufacturing a large-scale electronic equipment with high specific characteristics in the form of multichip modules (MCM).
At present, IC chip carriers on a film base, particularly on the polyimide film, have a wide spreading. A high thermal stability, stability of electrophysical and thermomechanical characteristics in operation, high mechanical rupture, tensile and breaking strength in the thickness range of 7 to 100 xcexcm, resistance to chemical attacks and high temperatures during technological treatment should be ascribed to advantages of the polyimide based carrier. Such carrier ensures an automation of mounting processes for chip with a large number of contact pads, since conducting paths on a carrier surface could be made with a high accuracy and disposed with a high density having a small, strictly fixed gap between them.
A one-layer carrier with spider leads is known, manufactured from the polyimide film with a copper or aluminum foil glued on it, in which foil conducting paths are etched by photolithography techniques. Chip contact pads are connected to the conducting paths by welding or soldering techniques, and other, free ends of those paths are used for measuring and subsequent welding or soldering to mating contacts in a package or to a circuit structure in a packageless mounting (A. Yu. Ber, F. E. Minsker.  less than  less than Mounting of semiconductor devices and integrated microcircuits greater than  greater than , Moscow,  less than  less than High School greater than  greater than  Publishing House, 1986, pp.147-150xe2x80x94in Russian).
A polyimide chip carrier is known, which is employed in manufacturing an electronic equipment based on packageless LSIC, comprising a system of rigidly oriented tape conductors (from copper or aluminum) of 20 to 30 xcexcm wide displaced on a surface of the polyimide film carrier and spaced in a chip area with a step compatible with a step of contact pads on the chip and in a carrier periphery with a step compatible with mating mounting pads on a circuit board. Besides, all conductors are represented by contacts displaced at carrier edges with a step compatible with a step of probe contacts in a measuring apparatus. Conductors being rigidly fixed relative to each other are welded to LSIC contact pads, and continuations of these conductors, after corresponding cutting, are welded or soldered to mating contact pads on the circuit board. Thus, each contact pad of the chip and its mating contact pad on the polyimide carrier along with a connecting element in the form of the conducting path on the polyimide carrier form a contact assembly intended for coupling electrically the chip contact with the mating contact on the circuit board. Prior to cutting the chip for mounting the chip onto the circuit board, the carrier with the chip is placed into a contact device of the measuring apparatus to monitor electrical and functional chip parameters and to reject imperfection chips (E. N.Panov,  less than  less than Peculiarities of assembling the application-specific high-integration IC""s on base array master chips greater than  greater than , Moscow,  less than  less than High School greater than  greater than  Publishing House, 1990, pp.77-78,xe2x80x94in Russian).
A two-layer carrier is known which has metallized paths in two layers separated by a polyimide insulation layer. Such carrier allows to mount chip having a large number of contact pads displaced along a chip periphery, including those displaced in two lines as on a chessboard (ibid, p.78).
A two-layer carrier on a flexible base, comprising a signal layer, layers of the supply bus and ground bus insulated from each other, is known. Conducting paths displaced on surfaces of polyimide carrier layers are coupled to each other by means of metallized vias made in the polyimide base of carrier layers. The coupling of conducting paths with IC chip contact pads is performed by means of welding.
Such carrier embodiment has permitted to avoid many problems inherent to carrier on a rigid base, particularly an impossibility to optimize signal buses and ground and supply buses within one layer, and to ensure a resistance to bending forces during technological operations ( less than  less than Second birth less than  less than  of the automated mounting of chips on a tape carrier. Express information on the abroad electronic technology. Part 43-45 (5205-5207) of Mar. 1-5, 1991, Moscowxe2x80x94in Russian).
While mounting onto the circuit board, contact assemblies in the polyimide carrier structure have electrical characteristics substantially better than corresponding characteristics of contact assemblies in cermet package structure (for which packages the way of the electric signal is: chip contact padxe2x80x94transitional wire elementxe2x80x94mating contact pad of a cross-armxe2x80x94transitional conductors in a multilayer circuit structure of the cermet packagexe2x80x94package output terminal) in basic electrical characteristics (a resistance value, a parasite terminal inductance and a parasite intra-terminal capacity). Besides, a usage of the polyimide carrier ensures a good matching of welded chip conductors and contact pads while mounting, which substantially improves an automation of mounting processes and reduces the cost of the chip mounting both in packages or within an equipment assemblies based on packageless ones.
However, the above one-layer, two-layer and three-layer polyimide chip carriers, solving tasks in improving the registration precision of contact pads and conductors and fixation of conductors relative to each other, in improving the electrical characteristics of contact assemblies elements, in combining processes of parameter measurements, rejection and mounting of chips on a circuit board in a single technological route, have the following substantial disadvantages:
technological processes (welding the tape conductors to contact pads of chips) are used in mounting, which can cause a defect formation in chips and reduction of their reliability characteristics in operation;
the welding process is a non-group operation, i.e. each welded contact is processed individually, serially one after another, which reduces sharply a mounting productivity and increases a probability of a welding machine malfunction, especially for multiterminal chips.
A technical decision most close to the present invention in the technical essence and obtained result when using is a chip carrier comprising a base from a dielectric material, polyimide, with conducting paths formed on its surface, to which said chip is glued so as to coincide contact pads with corresponding conducting paths on the carrier surface. After welding (or soldering) conducting paths to corresponding chip contacts, carrying out parameter testing and rejection of fit chips, a periphery chip area having measuring contact pads is cut off, and the remaining part of the carrier with the chip is positioned on a circuit board; then contact pads of a central carrier zone are welded (or soldered) to mating mounting pads on the circuit board (E. N. Panov,  less than  less than Peculiarities of assembling the application-specific high-integration IC""s on base array master chips greater than  greater than , Moscow,  less than  less than High School greater than  greater than Publishing House, 1990, p.78xe2x80x94in Russian).
The main disadvantages of this technical decision for complex multiterminal IC are:
a usage of the defect-creating welding process;
a non-group character of the mounting process.
The problem, for which solving the present invention is directed, is to provide a multiterminal chip carrier comprising contact assemblies of an original structure, which usage permit to exclude the defect-creating welding process and to make the process of connecting the conductors to the chip contact pads a group process, which leads to a significant reduction of a labor content and cost of a carrier assembling and chip mounting into a package or as a part of a multichip module for improving a quality, reproducibility and reliability of connections.
In addition, a usage of the proposed contact assembly permits to solve one of the main problems of multichip modules, namely the rejection of obviously fit chips prior to their mounting as a part of MCM, at the cost of improving the testability of packageless IC chips and ensuring a total chip testing through output terminals of the carrier.
The indicated technical result is attained at the expense of using special assemblies in the carrier structure, which ensure an electrical and mechanical coupling between contacts.
The set problem is solved with an attainment of the mentioned technical result by that in an IC chip carrier comprising a base of a dielectric material with a system of oriented and fixed conducting paths on its surface and contacts, ones of which are intended for connecting with mating chip contact pads and others are intended for connecting with mating contacts on a circuit board, which contacts are made in the form of metallized vias which top edges are coupled with the conducting paths on the top surface of the carrier base, and bottom edges of vias form contact assemblies in joints with the mating contact pads of the chip or, respectively, with mating contact pads of the circuit board filled with an electric-conductive binder, which assemblies together with conducting paths ensure an electric coupling of the chip contact pads with contact pads on the circuit board;
and also by that the metallized vias for the chip contact pads and for the contact pads of a multilayer circuit board are made of different diameters;
and also by that the metallized vias are made in the form of a cylinder;
and also by that the metallized vias are made in the form of frustums of a cone, the lesser bases of said frustums of a cone being faced to the contact pads on the surface of the chip or multilayer circuit board and the greater bases of said frustums of a cone being coupled with the conducting paths on the surface of the carrier base;
and also by that the metallized vias for contacting with the contact pads of the multilayer circuit board are made with metallized rings on the top and bottom surfaces of the carrier base;
and also by that the metallized vias in the carrier for the chip contact pads can be made in the form of an array displaced over the surface of the chip having contact pads coincided in their placement with the array of the carrier vias;
and also by that the carrier base is made from the polyimide film;
and also by that the carrier can be made multilayer;
and also by that the top edges of metallized vias coupled with the conducting paths on the top surface of the carrier base are made with metallized rings;
and also by that the conducting paths connecting the chip contact pads with the metallized vias at the periphery of the multilayer carrier are made in the form of strip lines;
and also by that several IC chips are disposed on one multilayer carrier.